1. Field of the Invention
The present invention relates to an individual real-image optical viewfinder separate from a photographic lens system.
2. Description of the Prior Art
The recent compact camera of a lens shutter system, as well as the single-lens reflex camera of an interchangeable lens system, is equipped with an automatic exposure control system (hereinafter referred to as "AE") and an automatic focusing system (hereinafter referred to as "AF"). The compact camera is equipped with an optical viewfinder system, an optical system for automatic focusing and an optical system for automatic exposure, which are separate from each other.
Some compact cameras are capable of photographing in either a normal mode or a trimming mode (pseudo telephoto mode) for obtaining a telephotographic print without varying the focal length of the photographic lens. When the compact camera is set for a trimming mode, the size of the field frame within the viewfinder is adjusted to a size corresponding to that for telephotography to indicate a printing area of the trimming mode, and trimming data is recorded in the margin of the film, an IC card, a semiconductor memory and so on. In developing a film carrying pictures taken by such a compact camera, the trimming data recorded on the film, the IC card and so on is read, and the frames of the film are trimmed and enlarged in conformity to the trimming data to obtain prints simulating telephotographic prints.
A camera capable of recording trimming data on the film, an IC card and so on for use in trimming and printing process is disclosed, for example, in U.S. Pat. No. 4,728,978.
Incidentally, when an optical viewfinder system, an optical system for AF and an optical system for AE are provided separately in a camera, the range of distance measurement and the range of light measurement indicated within the viewfinder deviate from the actual range of them due to parallax. Moreover, in a camera capable of photographing at a trimming mode, the actual range of distance measurement and the actual range of light measurement are different in size from the ranges of distance measurement and light measurement indicated in the object field of the viewfinder, when the size of the object field of the viewfinder is changed for photographing at the trimming ratio.
Furthermore, when a photographic optical system, an optical viewfinder system and optical systems for measuring distance or brightness are provided separately in a camera, the camera needs a large space for containing those optical systems. Thus, the separate arrangement of those optical systems in a camera under limitative conditions makes forming the camera in a comparatively small size difficult, increases the component parts, and places restrictions on the design of the external appearance of the camera.